93777-45-8Relevant academic research and scientific papers
N-Heterocyclic Carbene/Carboxylic Acid Co-Catalysis Enables Oxidative Esterification of Demanding Aldehydes/Enals, at Low Catalyst Loading
Berkessel, Albrecht,Biswas, Animesh,Harnying, Wacharee,Sudkaow, Panyapon
supporting information, p. 19631 - 19636 (2021/08/09)
We report the discovery that simple carboxylic acids, such as benzoic acid, boost the activity of N-heterocyclic carbene (NHC) catalysts in the oxidative esterification of aldehydes. A simple and efficient protocol for the transformation of a wide range of sterically hindered α- and β-substituted aliphatic aldehydes/enals, catalyzed by a novel and readily accessible N-Mes-/N-2,4,6-trichlorophenyl 1,2,4-triazolium salt, and benzoic acid as co-catalyst, was developed. A whole series of α/β-substituted aliphatic aldehydes/enals hitherto not amenable to NHC-catalyzed esterification could be reacted at typical catalyst loadings of 0.02–1.0 mol %. For benzaldehyde, even 0.005 mol % of NHC catalyst proved sufficient: the lowest value ever achieved in NHC catalysis. Preliminary studies point to carboxylic acid-induced acceleration of acyl transfer from azolium enolate intermediates as the mechanistic basis of the observed effect.
Study the Efficiency of Some Esters Based on 2- Ethyl Hexanoic Acid as Synthetic Lubricants
Kamal, Rasha S.,Nassar, Amal M.,Ahmed, Nehal S.
, p. 7191 - 7200 (2021/11/16)
Esters have many important properties, such as biodegradation, low toxicity, good thermal stability and excellent solvability, because these features are definitely the most versatile of the various types of base fluids currently available and can be modified to provide unique physical and chemical properties that can be designed to meet the lubricant industry's challenges. In this article, Reaction was prepared by various branched synthetic esters of 2- ethyl hexanoic acid with different 2 groups of alcohols, the first one (1-hexanol, 2- ethyl hexanol,1-octanol, 1- dodecanol and 1- hexadecanol), and the second group (neopentyl glycol, trimethylol propane and pentaerythritol). All the preparation compound form were confirmed by examine the physical and chemical properties as (Nuclear Magnetic Resonance, Infra-Red Spectroscopy, Total Acid Number, Density, Thermo Gravimetric Analysis TGA, Specific gravity, Reflective index, Molecular weights estimation and flash point). As a synthetic lubricating oil, the performance of these compounds was studied. Prepared compounds have been found to contain low pour point (PP), high viscosity level (VI) and Newtonian fluid for rheological behavior.
A microwave-assisted highly practical chemoselective esterification and amidation of carboxylic acids
Pathak, Gunindra,Das, Diparjun,Rokhum, Lalthazuala
, p. 93729 - 93740 (2016/10/21)
The ubiquitousness of esters and amide functionalities makes their coupling reaction one of the most sought-after organic transformations. Herein, we have described an efficient microwave-assisted synthesis of esters and amides. Soluble triphenylphosphine, in conjugation with molecular iodine, gave the desired products without the requirement for a base/catalyst. In addition, a solid-phase synthetic route is incorporated for the said conversion, which has added advantages over solution-phase pathways, such as low moisture sensitivity, easy handling, isolation of the product by simple filtration, and reusability. In short, our method is simple, mild, green, and highly chemoselective in nature.
